Benefits of repeated apt cache cleans

In the quest for ever smaller Docker images, it's common to remove the `apt` (for Debian/Ubuntu based images) cache after installing packages. Something like ``` RUN rm -rf /var/lib/apt/lists/* ``` I've seen a few `Dockerfile`s where this is done after each package installation ([example][1]), i.e. with the pattern ``` # Install some package RUN apt-get update \ && apt-get install -y <some-package> \ && rm -rf /var/lib/apt/lists/* # Do something ... # Install another package RUN apt-get update \ && apt-get install -y <another-package> \ && rm -rf /var/lib/apt/lists/* # Do something else ... ``` Are there any benefits of doing this, rather than only cleaning the `apt` cache at the very end (and thus only updating it once at the beginning)? To me it seems like having to remove and `update` the cache multiple times just slows down the image build. [1]: https://github.com/docker-library/python/blob/6a981ebc3ba38d0668db58813f309e58763438e1/3.8/buster/slim/Dockerfile